<!DOCTYPE html>
<html>
   <head>
     <link rel="stylesheet" href="3.20css"/>
    <style>
        P{
            font-size:28px;
            color:green;
        }

        </style>

        <style>
            p{
                font-size:14px;
                color:blue;
            }
            P{
                margin:10px;
                padding:5px;
                color:green;
                font-size:12px;
            }
            #P2{
                color:blueviolet;
            }
            .p3{
                color:darkred;
            }
            </style>
            </head>
    <body>
        <h1>这是标题</h1>
        <p style="font-size: 50px;color:red;">这是段落1</p>
        <p id="p2">这是段落2</p>
        <p class="p3">这是段落3</p>
        <p class="p3">这是段落4</p>
        <p id="p2">这是段落5</p>
        <p id="p2">这是段落6</p>
        </body>
</html>